This invention relates generally to machine vision systems and specifically to real time data modifier apparatus and methods for use in machine vision systems.
Substantial development work has been performed on applying machine vision to industrial automation such as automated inspection of two dimensional or three dimensional articles. In general, machine vision systems currently available operate by thresholding a grey scale video camera pixel data stream into a binary data stream and then storing one frame of binary video data in an image buffer. The stored binary image is then processed in an image processing system, usually by first subjecting the stored image data to runlength encoding for data compression and then processing in hardware or software processing systems the run-length encoded data in accordance with a plurality of image analysis algorithms. This image processing step is utilized to extract essential features of the image such as area, perimeter, center of gravity, number of image blobs, image blob location, size, etc.
The speed at which a machine vision system can perform a preprogrammed automated part inspection task is highly dependent on the complexity of the image data which must be processed and the number of image features which must be extracted from the image data for comparison purposes to achieve a statistically reliable decision on acceptance or rejection of the part. The application of machine vision systems to inspection of structurally complex parts is often not commercially attractive because of long image processing time. The use of machine vision in other applications such as, for example, visual servoing of robot manipulator limbs for part insertion or part orientation has also been impeded by the long image processing time required to analyze a complex scene.